“It seems like the child is really thriving as a little boy instead of as a little girl,” said Dr. Joel Lazar, who specializes in gender-related issues.

Lazar says children can start to understand whether they're a boy or girl between ages three and five, and it's not necessarily based on their bodies.

“At that age, she's so naive as to what it really means to be a boy or a girl, that you feel like at least at that point it's genuine,” Lazar said.

Lazar says the transition is not easy for everyone as studies show. There's an increased risk of suicide attempts and depression for transgender people.

He adds the experience can also be challenging for the parents.

“You want to honor what seems to make your child happy, and obviously, as a parent, we have to look at the bigger picture and say OK, at the end of the day, is this really what's gonna be best for your child?”

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